Apply setImageLayout() to all of a VkImage's subresources.

include/gpu/vk/GrVkTypes.h

Index: include/gpu/vk/GrVkTypes.h
diff --git a/include/gpu/vk/GrVkTypes.h b/include/gpu/vk/GrVkTypes.h
index ac33bf8dad3400a7c7bc845e3692c3fce846c7af..2e6a2556303c19fafe4a4e803dea9f6ba832f055 100755
--- a/include/gpu/vk/GrVkTypes.h
+++ b/include/gpu/vk/GrVkTypes.h
@@ -36,6 +36,7 @@ struct GrVkTextureInfo {
     VkImageTiling  fImageTiling;
     VkImageLayout  fImageLayout;
     VkFormat       fFormat;
+    uint32_t       fLevelCount;
 };
 
 GR_STATIC_ASSERT(sizeof(GrBackendObject) >= sizeof(const GrVkTextureInfo*));